 Professor of Pharmaceutical Sciences and Chemistry
B.S. 1988, Calvin College
M.S. 1990, The University of Chicago
Ph.D. 1994, The University of Chicago
NIH Post-Doctoral Fellow 1996, Columbia University
Room: 7111 Rennebohm
Phone: 608-260-1063
Email: rphsung@pharmacy.wisc.edu
Position: Professor
Zhang, Y.; DeKorver, K. A.; Lohse, A. G.; Zhang, Y.-S.; Huang, J.; Hsung, R. P. "Synthesis of Amidines Using N-Allyl Ynamides. A Palladium-Catalyzed Allyl Transfer via an Ynamido-pi-Allyl Complex. " Organic Lett. 2009, 11, 0000-0000.
Song, Z.; Lohse, A. G.; Hsung, R. P. "Challenges in the Synthesis of a Unique Mono-carboxylic Acid Antibiotic (+)-Zincophorin." Nat. Prod. Rept. 2009, xx, 0000-0000.
Zhang, Y.; Long, Q. A.; Gerasyuto, A. I.; Hsung, R. P. "A General Approach to the Quinolizidine Family of Alkaloids via an Intramolecular Aza-[3 + 3] Annulation. Synthesis of (±)-2-Deoxy-Lasubine II." Synlett 2009, 237-240.
You, L.; Hsung, R. P.; Bedermann, A. A.; Kurdyumov, A. K.; Tang, Y.; Buchanan, G. S.; Cole, K. P. "An Enantioselective Synthesis of the ABD Tricycle for (-)-Phomactin A Featuring Rawal's Asymmetric Diels-Alder Cycloaddition." Adv. Syn. Cat. 2008, 350, 2885-2891.
Li, G.; Hsung, R. P.; Slafer, B. W.; Sagamanova, I. K. "Total Synthesis of (+)-Lepadin F." Organic Lett. 2008, 10, 4991-4994.
Tang, Y.; Shen, L.; Dellaria, B. J.; Hsung, R. P. "Saucy-Marbet Rearrangements of Alkynyl Halides in the Synthesis of Highly Enantiomerically Enriched Allenyl Halides." Tetrahedron Lett. 2008, 49, 6404-6409.
"Synthesis of the C1-C23 Fragment of Spirastrellolide A." Yang, J.; Liu, J.; Hsung, R. P. Organic Lett. 2008, 10, 2525-2528.
Ko, C.; Feltenberger, J. B.; Ghosh, S. K.; Hsung, R. P. "Gassman's Intramolecular [2 + 2] Cationic Cycloaddition. Formal Total Syntheses of Raikovenal and Epi-Raikovenal." Organic Lett. 2008, 10, 1971-1974.
Al-Rashid, Z. F.; Hsung, R. P. "Reactive Intermediates from DMDO-Oxidation of Ynamides. Trapping of a De Novo Chiral Push-Pull Carbene via Cyclopropanation." Organic Lett. 2008, 10, 661-663.
Lu, T.; Song, Z.; Hsung, R. P. "A Mutually pi-Facial Selective Cyclopropanation of Chiral Enamides Using Dirhodium(II) Carbenoids." Organic Lett. 2008, 10, 541-544.
Hsung, R. P. "An Unexpected Reversal of Diastereoselectivity in the [4 + 3] Cycloaddition reaction of Nitrogen-Stabilized Chiral Oxyallyl Cations with 2-Furoates." Antoline, J. E.; Synlett 2008, 739-744. [An Invited Article for the Cluster Communications on "Chemistry of Allenes and Alkynes." Hisashi Yamamoto, Ed.]
Al-Rashid, Z. F.; Johnson, W. L.; Hsung, R. P.; Wei, Y.; Yao, P.-Y.; Liu, R.; Zhao, K. "Synthesis of a-Keto-Imides via Oxidation of Ynamides." J. Org. Chem. 2008, 73, 8780-8784.
Yao, P.-Y.; Zhang, Y.; Hsung, R. P.; Zhao, K. "A Sequential Metal-Catalyzed C-N Bond Formation in the Synthesis of 2-Amido-Indoles." Organic Lett. 2008, 10, 4275-4278.
Zhang, X.; Hsung, R. P.; Li, H.; Zhang, Y.; Johnson, W. L.; Figueroa, R. "A Highly Stereoselective Synthesis of Chiral a-Amino-b-Lactams via the Kinugasa Reaction Employing Ynamides." Organic Lett. 2008, 10, 3477-3479.
| Research Description
. [4 + 3] Cycloaddition Chemistry of Allenamides. We have been examining extensively"the chemistry of 1-amidoallenes, or allenamides, and developed several major reactions associated with this new class of allenes. Most significantly, we achieved a tandem epoxidation and oxyallyl cation [4 + 3] cycloaddition using chiral allenamides. The epoxidation of allenamides proves to be an excellent source of chiral, nitrogen stabilized oxyallyl cations. We were able to develop highly regio- and stereoselective inter- and intramolecular oxyallyl cation [4 + 3] cycloadditions, and, very recently, we achieved the first asymmetric [4 + 3] cycloaddition using copper-bisoxazoline systems.
II. Stereoselective Methods Using Chiral Ynamides. In a related but different area, we have developed the chemistry of ynamides as stable equivalents of Ficini's ynamines. Our work has rekindled the interest of the synthetic community toward this very interesting class of functional group. We have placed particular emphasis on developing a highly efficient synthesis of ynamides in order to provide the kind of accessibility that may allow the community to view ynamides as a user-friendly functional group in organic synthesis. Toward this goal, we developed a Cu(II)-catalyzed C-N bond formation involving sp-hybridized carbons. This catalytic amidation provides a direct entry to chiral ynamides via N-alkynylation of amides and should have an impact on the future synthetic utility.
III. Natural Product Total Syntheses. We have developed a bio-inspired [3 + 3]-annulation reaction or formal cycloaddition of vinylogous amides or diketones with alpha,beta-unsaturated iminium salts that can be used to construct heterocycles]. The transformation involves a tandem Knoevenagel-6-pi-electron electrocyclic hetero ring-closure. This process has allowed us to achieve numerous total syntheses of complex natural products such as arisugacin A, tangutorine, hongoquercin A, perhydrohistrionicotoxin, cylindricines, and rhododaurichromanic acids.
IV. Ketal-Tethered Reactions and Natural Product Syntheses. Ketal-tethered intramolecular reactions, specifically intramolecular Diels-Alder [IMDA] and RCM reactions, which are areas that have not been widely studied, are discussed here, as well as an approach to fusidilactone C and spirastrellolide A, spiroketal-containing natural products that first provoked our interest in ketal tethered strategies. These investigations are of significance because they can lead to conceptually and fundamentally different approaches to spiroketal-related complex natural products.
Last updated February 9, 2006.
Visiting Professor at Tianjin University [P. R. China], 2005 - 2007. The Camille Dreyfus Teacher-Scholar, 2001. McKnight Faculty Award, 2001 - 2003. National Science Foundation Early Career Development Award, 2001 - 2006. RW-Johnson Pharmaceutical Research Institute Faculty Award, 1998 - 2000. National Institutes of Health Postdoctoral Fellow, 1996 - 1997.
|
